Detailed in Richard Kaufman's JENNINGS '67 (1997), p. 23, is a devilishly clever technique for obtaining a break beneath the top card of a deck. In the introduction to the book (pp. 12-13), Mr. Kaufman states that Mr. Jennings attributed the technique to Lin Searles, but that no published record could be found.

Today, however, I was looking through Stephen Minch's SECRETS OF A "PUERTO RICAN GAMBLER" (1980), when I spotted a technique that is very similar. Referring to page 90, I quote:

Daryl came up with a one-handed method for obtaining a break under the top card of the deck many years ago. Harvey Rosenthal developed the same concept independently in Washington, D.C. and published it in his "Packet Switches" book.

I found Karl Fulves' PACKET SWITCHES (PART THREE) (1977) and found the Rosenthal technique, "The Pop-up Move" (pp. 184-186). All three techniques appear to be very similar, if not identical.

I'm not sure if the previous techniques by Daryl and Mr. Rosenthal were missed when preparing JENNINGS '67, but it seems a bit unlikely, as both Mr. Minch, who wrote SECRETS OF A "PUERTO RICAN GAMBLER", and Mr. Rosenthal, who developed the technique, edited JENNINGS '67.

Did both of them miss the technique when editing, or is there a difference that I'm not spotting?

I am in no way trying to put down the work of any of the aforementioned people. I was just wondering if the techniques differ in some way.

The Daryl and Rosenthal techniques are identical. They have nothing in common with the Searles technique, Autobreak. With the latter you simply press down on the outer left corner of the deck, causing the right long side of the top cards to rise. You must either have a reversed card or a bridged card to do it.The Rosenthal technique is an entirely different way to obtain a break.